Re: Boeing 777 goes up in flames

The engine housing, seen from the front (elsewhere), suggests possibly a fan blade sheared off.

If it has, that will raise serious concerns about the safety of those engines - especially after the disappearance of MH370. You don't just disassemble a turbofan on the runway for maintenance, those things are specialist jobs that take days / weeks to dismantle and service. The engine blades are also slotted into place and theoretically they cannot come loose so if one has, then boeing have a serious problem to deal with.

• Initial examination of the left engine revealed multiple breaches of the engine case in the area around the high pressure compressor.• Examination of the material recovered from runway found several pieces of the high pressure compressor spool (approximately 7-8 inches in length).

Re: Boeing 777 goes up in flames

The most worrying aspect of this short, initial report is that it looks like the engine failure was uncontained.If an engine breaks, the casing is designed to stop any bits of metal flying out and damaging the rest of the aircraft, including the fuel tanks and critical wiring.Uncontained problems can be very serious.As for the part that appears to have broken, the high-pressure compressor spool, Dr Colin Brown from the Institution of Mechanical Engineers told me that it's "most likely" to be from a "fatigue crack".

Re: Boeing 777 goes up in flames

fatigue cracks, engines blowing themselves to bits through indestructible engine cowlings and planes vanishing mid flight... It's really not looking good for Boeing is it.I suspect they've already had several fingers pointed at them recently in light of MH370, this won't do them any good at all.

Re: Boeing 777 goes up in flames

The casing should contain any damage but spool parts, about 7-8in in length, were found on the runway.

Thrust is thrust regardless of what is around it. If you got a turbofan pushing thousands of pounds of air out the back and something breaks, it's naturally going to fly out the back with the air flow. It isn't necessarily going to fly out sideways as there is a fight between centrifugal force and rearwards thrust going on. The only way to stop things flying out the end would be to cover it up.. blocking the thrust (and the point of the engine) in the first place.

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The part that appears to have broken, the high pressure compressor spool, is a circular disc that spins at very high speed.It's designed to never break, because if it does the tough outer casing of the engine can't contain the bits of metal that will come flying out

Designed to never break? What do I keep saying about people and experience just lately. You can have the best engineers on the planet say something with 100% certainty but it doesn't mean they're right. This unbreakable thing just flaming broke! The titanic was unsinkable... and you can still see it today as a tourist.. on the bottom of the ocean floor in pieces via a specialist submersible

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Investigators need to find out how new the part was, when it was last checked, and whether it broke because something hit it, maybe a bird

We all know bird strikes and turbofans are a bad mix.. but breaking the unbreakable shouldn't be possible... if anything I'd expect the bird to be a mini sliced and BBQ'd turkey as it came out the rear end.

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Dr Colin Brown from the Institution of Mechanical Engineers has told me that, although you can't rule out a bird strike at this early stage, it's "most likely" to be from a "fatigue crack".

In an unbreakable part

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The critical question now, is this a one-off or is it a problem that could arise in similar engines?

MH370 was the first thing that entered my mind the moment i heard about this story.